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carbon dioxide

carbon dioxide

95 2.3
A colorless gas without smell that people and cars make and plants use to make oxygen
  • noun
  • /ˈkɑrbən daɪˈɒksɪd/
translation icon : dióxido de carbono
  • Every time we exhale, we release carbon dioxide into the air.
  • carbon dioxide emissions
  • carbon dioxide (CO2)
  • carbon dioxide concentration

Well, I couldn't expel the carbon dioxide and breathe it out.

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Examples

  • Most of the atmosphere is made up of carbon dioxide, and just 0.13 of it is oxygen.

    Academic text (1990)
  • But still, the main part of the problem is the emission of carbon dioxide from the burning of coal, oil, and gas.

  • At the moment, the carbon dioxide is the issue, not the waste heat.

  • What comes out you have carbon dioxide and water.

  • Now, the trees convert the carbon dioxide.

  • But in this atmosphere it's in the form of carbon dioxide.

  • When trees grow, they naturally absorb carbon dioxide from the atmosphere.

  • The burning of fossil fuels has increased the carbon dioxide content of the atmosphere.

    Academic text (1999)
  • As vegetation dies and soil is disturbed, emissions of carbon dioxide will increase.

    Academic text (1993)
  • When we started, fossil fuel burning pumped six billion tons of carbon dioxide into the air every year.

    Fiction book (2001)

Synonyms

CO2
vscarbon dioxide
  • Specialized
174 2.6

A colorless gas people breathe out and plants use to make food

means the same but is the short scientific label
carbonic acid gas
vscarbon dioxide
  • Archaic
5.7

A colorless, odorless gas called carbon dioxide that plants use to make food

means the same but is the modern preferred term

Surface Forms

Morphology

carbon + dioxide

The noun is compositionally built from 'carbon' (the element) + 'dioxide' (a compound containing two oxygen atoms), so the overall meaning — the dioxide of carbon (CO₂), a gas produced in respiration and combustion — is directly derivable from the parts. This chemistry naming pattern is systematic and common across languages, so a B1 learner who knows both constituents would readily infer the MWE's meaning.

Etymology

Carbon dioxide comes from the name parts carbon and dioxide, where dioxide means 'two oxygen atoms'. It is the gas made when things burn or when animals breathe out, and plants take it in to make food, so that's why we use this word for the gas that affects the air today.